Cooking oils are an essential ingredient when you're sautéing, frying, or baking your favorite foods, but did you know that using specific kinds of oils might actually be causing your waistline to balloon?
While certain oils are packed with healthy vitamins and nutrients, others can make you fat. The worst offender—soybean oil—may sound healthy, but the popular vegetable oil that's being consumed at an alarming and unhealthy rate is a nutritional nightmare that's been shown to contribute to significant weight gain in animals.
In fact, University of California researchers came to this discovery in 2015 when they divided mice into four groups fed each of them diets comprised of 40 percent fat and the same number of calories.
Two groups were fed a diet rich in coconut oil, a popular source of saturated fat, and one of those groups were also given fructose, a type of sugar. The other mice were given a soybean oil-heavy diet, equal to the amount a typical American consumes, and one of the two soybean groups was also given fructose.
What the researchers discovered was that mice on the soybean oil diet gained 25 percent more weight than mice on the coconut oil diet, and 12 percent more than groups who were also given fructose. The mice on the soybean oil diet also developed larger fat deposits and were more likely to become diabetic. In other words, the specific type of fat the mice ate made a difference, and soybean oil was no good.
At the time, researchers hypothesized that soybean oil was harmful on account of its high omega-6 fatty acid content, particularly linoleic acid, an omega-6 fatty acid that makes up approximately 55 percent of soybean oil. While our bodies need some omega-6s for optimal health, too much can increase appetite and slow the rate at which the body burns fat, leading to weight gain. To combat weight gain, study up on these 100 Best Weight Loss Tips!
A 2017 study published in Nature Scientific Reports further bolstered this hypothesis, and found that while genetically-modified (GM) soybean oil that's used in restaurants and engineered to have low linoleic acid induces less obesity and insulin resistance than conventional soybean oil, its effects on diabetes and fatty liver are similar to those of conventional soybean oil. Again, that's believed to be because of the omega-6s.
What's more? Omega-6 is an inflammatory fat, meaning it causes inflammation in the body. While inflammation is a natural, protective part of the body's immune response, it's only protective in low doses. Constant inflammation, on the other hand, can cause weight gain, drowsiness, skin problems, digestive issues, and a host of diseases, including diabetes, cancer, and depression.
So what does all of this mean for your consumption of vegetable oil? Since most Americans over consume vegetable-oil-laden products and have damaging omega-6 to omega-3 ratios, it's best to minimize your use of oils that are heavy on omega-6s.
Instead of relying on one type of vegetable oil when you cook, prepare food, or make sauces and salad dressings, get in the habit of rotating between oils. That way you can use some vegetable and canola oil, but also make use of healthier sources of fat such as extra virgin olive oil, avocado oil, coconut oil, and grass-fed butter. Speaking of good sources of fat, be sure to check out this list of 20 Healthy Fats to Make You Thin!